Epoché (εποχη) (European transcription epochè or epokhé) is a Greek term which describes the theoretical moment where all belief in the existence of the real world, and consequently all action in the real world, is suspended. One's own consciousness is subject to immanent critique so that when such belief is recovered, it will have a firmer grounding in consciousness. This concept was developed by Aristotle and plays an implicit role in skeptical thought, as in René Descartes' radical epistemic principle of methodic doubt. The prominent phenomenological philosopher Edmund Husserl picks up the notion of 'phenomenological epoché' in his influential work Cartesian Meditations where the world is 'lost in order to be regained' through placing the epoche and thereby 'bracketing' the world.

Epoché played an interesting role in the Pyrrhonism philosophy of Pyrrho. On the basis of claiming that we do not know anything, Pyrrho argued that the preferred attitude to be adopted is Epoché, i.e., the suspension of judgment or the withholding of assent. It is not true that the result of this is an embrace of the idea that we have no rationale to chose one way of action of another; rather, one kind of life or one kind of action cannot be definitively said to be the 'correct' way or action but instead of the Skeptic suggesting a life of inaction he/she insists that one ought to live according to customs, laws, and traditions. Also, it is important to note that the Skeptics do not dogmatically assert the inability to know anything: the very word SKEPSIS means 'always searching/investigating'--it would, indeed, be counter-intuitive to boldly assert that nothing can be known since that very proposition itself would then be elevated to the status of something which is known.